CNN reports Japanese officials on Sunday criticized Carlos Ghosn's escape from the country.<br />Calling it 'unjust', Japan vowed to tighten immigration rules in their first public remarks since the former auto executive fled for Lebanon a week ago.<br />Japan's top justice official, Justice Minister Masako Mori, said Ghosn left Japan illegally by unjust methods.'<br />She said that there is no official record of Ghosn's departure from Japan, and that prosecutors are investigating the case.<br />Justice Minister Mori also said she's ordered Japan's immigration department to further tighten rules for leaving the country.